1. Field of the Invention
The present invention generally relates to methods employed to facilitate the painting or finishing of window frames. More specifically, this invention relates to a method for masking a window in a window frame to be painted which employs an apparatus capable of accurately placing a temporary bonding agent between the window pane and a protective sheet which protects the window pane while the window frame is spray painted.
2. Description of the Prior Art
The necessity of painting window frames is a task that both painting contractors and homeowners alike find tedious and time-consuming. The primary reason for this is the desire to fully cover the window frame while at the same time avoiding getting the paint on the window pane itself. Paint which otherwise gets on the window pane must be thoroughly removed, particularly if the paint is oil-based. Particularly for a builder of new homes, removal can be time-consuming and cost intensive, at times requiring the use of a paint thinner. As a result, great care must be taken where the frame and the pane meet, generally necessitating a finer brush than normally used elsewhere.
When it is a paint contractor who is confronted with painting a window frame, time is a primary concern for purposes of cost-efficiency and competitiveness. The time needed to carefully paint around a window pane, multiplied by the number of windows to be painted, quickly adds up to a substantial amount of time lost for other jobs. In applications other than window frame painting, paint contractors are able to employ spray painting devices which greatly accelerate the process, making the contractor more cost-efficient and competitive with other contractors. However, for practical purposes window frames cannot be spray painted without providing some form of protection for the window pane. Traditionally, any advantage achieved in time by spray painting window frames has been offset by a considerable cost in time and money for additional work crews to remove the overspray from the window glass.
It is known in the art to mask the window pane by taping a paper covering over the window pane such that only the window frame is exposed. A paint sprayer can then be used to paint the window frame without getting paint on the window pane. However, a significant disadvantage to this method is that it is labor intensive and costly since it is time-consuming and difficult to remove the tape from the window pane once the paint has dried. Under most circumstances, the covering will be attached to the window pane well in advance of the actual time that the windows will be painted. Depending on the working environment, over time the tape may harden or become extremely tacky, thus making it very costly and difficult to remove the tape and its adhesive residue from the window pane. Again, paint contractors will find that any time and cost savings realized with spray painting will be offset by clean up costs.
Another disadvantage to the above method is that the use of a paper covering blocks the natural light coming in through the window, thus requiring artificial light sources to be used during the painting process. The use of a transparent cover, such as a thin sheet of plastic, with the above process is generally impractical because the plastic is more difficult to handle for one person alone, particularly while simultaneously trying to tape the plastic sheet to the window pane. Moreover, the tape tends to permanently adhere to the plastic sheet preventing reuse of the plastic sheet and producing excessive waste and costs to the contractor.
Therefore, it would be desirable to provide a method for masking a window by temporarily adhering a protective sheet to the window pane in which the sheet can be readily applied and removed by one person. Such a method would preferably employ the use of a temporary bonding agent as a substitute for the tape previously used. However, an applicator device would be needed which is able to accurately and quickly deposit the bonding agent relative to the window frame so as to securely bond the edge of the protective sheet along the window frame. In addition, it would be desirable to locate a predictable quantity of bonding agent such that the bonding agent would extrude out from beneath an undercut protective sheet and extend to cover the remaining exposed glass adjacent the window frame.
The prior art teaches various types of applicator devices for dispensing viscous fluids for numerous applications, including caulking compounds, lubricants and paints. Generally, the teachings of the prior art are primarily concerned with providing an applicator nozzle for controlling the flow of the viscous fluid to ensure that a sufficient quantity of the fluid is deposited on a surface in a way that is tailored to the specific geometric features of the surface. An example of this approach is U.S. Pat. No. 2,930,061 to O'Neil. O'Neil teaches a combined nozzle and spreader which conforms the flow of a lubricant to a cylindrical surface. In particular, the combination ensures that a thin film will be uniformly applied to the cylindrical surface for achieving thorough lubrication.
U.S. Pat. No. 4,957,225 to Childers and U.S. Pat. No. 4,946,081 to Jacobson are both directed to applicator nozzles for sealing compounds, such as caulk. Childers teaches a nozzle tip which is inclined with respect to the longitudinal axis of the nozzle. The purpose of the incline is to provide a nozzle tip which is self-wiping and which produces a smooth bead. Childers also employs a caulking-type gun which applies a predictable force to the cartridge containing the caulking compound, allowing a practiced user to anticipate the flow rate of the caulk. In contrast, Jacobson emphasizes the ability to provide a controlled flow rate of compound to the surface on which the compound is deposited by dispensing the compound through an auxiliary aperture which adjoins the primary aperture in the nozzle. The nozzle taught by Jacobson can therefore be directly abutted against the surface to which the caulk is applied and eliminates the influence on the flow rate due to the gap between the nozzle and the surface.
In a rather unconventional approach to controlling flow, U.S. Pat. No. 1,866,295 to Christman teaches a pumping unit which pumps paint through a nozzle for use in paint striping operations. The pump produces a metered flow which corresponds to the speed at which the nozzle is passed over the surface to be painted. The pump is driven by a large wheel which can be used as a guide to facilitate the formation of a straight paint stripe.
An applicator apparatus more related to window caulking is taught in U.S. Pat. No. 2,815,895 to Reed. Reed teaches a nozzle for dispensing window putty in the joints of a window frame or sash. Again, the emphasis is on controlling the quantity of the fluid dispensed. The nozzle is intended to be replaceable and has a predetermined orifice shape adapted to a specific application.
From the above discussion, it can be readily appreciated that the prior art does not disclose an applicator device which is adapted to accurately deposit a bonding agent a predetermined distance from a window frame for purposes of masking a window pane. In contrast, the prior art are each concerned with the particular quantity in which the viscous fluid is applied for purposes of appearance or uniformity. None of the references teach or suggest using an applicator nozzle having a geometry adapted for use as a guide when accurately applying a bonding agent adjacent the perimeter of a window pane. Nor are any of the prior art directed to the problems associated with depositing a protective coating on window frames.
Accordingly, what is needed is a method for masking a window pane which is time and cost-efficient, and which allows the window frame to take on a sprayed protective coating instead of being brushed. In order to fulfill this need, what is further needed is an applicator apparatus capable of accurately placing a suitable bonding agent on the window pane for masking the window pane in a manner that protects the window pane and yet leaves the window frame fully exposed.